TR6 TR6 Coolant System Problem

[ichthos]

I have a car that had sat for many years. I knew the engine coolant system would be dirty. I flushed the engine (many times) by installing one of those kits you use with your garden hose. When I ran the car it still ran hot. I put in a new water pump (there was a slight leak) and thermostat. I cleaned the pump housing. I cleaned out the heater pipe. I had the radiatior cored. I pulled out the heater core and flushed it. It started to run cooler after that, but my engine is still overheating. It warms up to about a third on the temperature gauge and stays there for a while. After about 45 minute at 70 MPH the temperature gradually starts to increase. After about two hours of driving (the longest I have taken it so far) it makes it to about 2/3 on the temperture gauge. I read my Bentley manual which recommended that I also remove the drain plug when flushing the coolant sytem. The problem? I removed the plug and nothing comes out. I cleaned the drain and the drain hole it fits into. All I can get is an occasional drop of water coming out of it. I am guessing that this may be my problem at this point. What can I do to open this area up? Obviously the flushing is leavning blind spots. How can I deal with this without tearing the engine apart? I am trying to get my car ready for a cross country road trip next summer and this would be a major problem. Any suggestions would greatly be appreciated.
Thanks, Kevin

 

[cnsky54]

I used to fix old farm tractors with the same problems. Too much scale packed around the cylinder sleeves. We had a cone-shaped tapered rubber nozzle (sorry, don't remember the make) that our garden hose hooked onto, but also a compressed air line from our tank. It fit into a bottom rad hose, and blew pressurized bubbly water into the block. Take the thermostat out and everything flushed out the top. Got a lot of crud out. Failing that, popping out the block frost plugs and digging a bit helped loosen the hardest stuff. Back cylinders were especially packed due to lower water flow over the years.

 

[Guest]

Kevin, I know at this point you are pretty frustrated. Of course, the ideal thing to do at this time would be to pull the engine, break it down, and clean the block the proper way. Since this doesn't appear to be an option, have you tried poking around inside this drain hole (the one right above the starter motor, right?) with a stiff wire. How about hooking your high-pressure water hose up to the heater outlet on the head, remove the thermostat and let the water come out here, periodically poking and scraping with the wire in the drain hole, replugging it, and flushing. Totally bypass your heater core and radiator core so as not to dislodge crap into these tight spaces.

Man, I feel for you and I understand your frustration. Water should definately gush out this drain hole so something is scaled or rusted over this area.

You might be able to accomplish this in your driveway, even leaving both manifolds on. Just be prepared to get wet. Definately seal off your starter motor with a plasic bag. Do not break a wire off in this hole or you will be pulling the engine. Just follow the path of flow of the engine coolant and improvise whatever water connections you can to get a flushing movement of water through the block. Short of that, and an occasional taping with a small hammer, not sure if the crud will come unless you "boil" the whole block.

All this, of course, without your engine running. Remember, just trying to feel why your drain hole is not draining. Not trying to do the undoable.



You do have the correct radiator cap installed, right?

Bill

 

[swift6]

There are also some pretty nasty flushing products out there that could clear it out. BG makes one that works pretty well but its expensive and is pretty toxic.

 

[ichthos]

Thanks everyone. I'll try your advice and see what happens. To answer some of your questions, yes, I did take off the thermostat housing the first time I back flushed it. I am going to be putting in a lower thermostat and a new sensor anyway, so I'l try it again. I did try poking around with a wire in the drain plug but can't feel where the hole goes. I had it up to a one drop per second when the car was running, but then it plugged again. I may try removing the freeze plugs, but sense I do depend on this car for transportation, I'll have to wait until I get the new plugs. I do have the correct radiator cap - I ordered it from Moss. Thanks again, and I'll let you know what happens.
Kevin

 

[Andrew Mace]

Before you go tearing the motor apart, get aggressive with that probe wire, or switch to a small screwdriver. You're not going to hurt anything in there, and eventually you WILL start to break through the crud. When you do, keep going until water GUSHES out; don't just settle for a "good" flow. In my experience (done this on many Triumphs), this will pretty much cure the problem. You might want at some point to repeat the chemical flush, though, just to help loosen even more of that crud.